The problem with me trying to write a detailed set of instructions is that they depend on your setup and library structure which I do not know. Also, I am really do not know much about using JRMC beyond just figuring out how to make this work. @bflat provided the basic information in this post:
http://www.head-fi.org/t/780642/onkyo-dp-x1-dual-sabre-dacs-balanced-sabre-btl-amp-mqa-dsd-256-android-5/9780#post_12687935.
A big part of this is that the playlists created can only include tracks that are on the same sdcard. If you want to create a playlist that includes tracks on both cards, you must split that list into two parts at this point. Export the playlist from JRMC as
M3U Playlist (simple). If you have split the playlist into sdcard specific parts be sure to identify each part in the name (-1 or -2).
- Load the playlist into a text editor and edit the file path to match the file paths on the DP-X1. In my case, /Volumes/Music/Music Libraries/DAP Music Library (2 SD Cards)/SD1/Classic Country/Hank Williams/Hank Williams - 40 Greatest Hits/1-03 Lovesick Blues.m4a gets changed to Classic Country/Hank Williams/Hank Williams - 40 Greatest Hits/1-03 Lovesick Blues.m4a.
- Save the edited playlist from the text editor using Save As with the settings Line Breaks = Windows (CRLF) and Encoding = Unicode (UTF-8).
- Copy the playlist to the root directory of the sdcard its tracks are on.
- Open the DP-X1 Player and wait for the library scan to complete. Go to the playlist section of the library. At the bottom of the list will be an Android section that should include your playlist. While I have described this for a single playlist, you can load all of your playlists in their respective sdcard root directory and they will all show up in the list.
- Select your playlist and play the first track.
- Go to the play queue and use the Save as playlist function to turn the queue into a saved playlist. If you had to split you original playlist into two parts because of tracks on multiple sdcards, long press the second part and select Add to the playlist and add it to the playlist you just created.
- Delete the playlist from the root directory of the sdcard
Your playlist will now be available in the DP-X1 library and the Android section playlists will be gone from the list (because you deleted them from the sdcards). Why not just use the Android section playlists? @bflat explains that in his post. This is really all his work, not mine. I use Text Wrangler to edit the playlists and it works very well for a free editor. Good luck.